Electrical condenser



Oct. 20, 1936. I F. H. POTTER ET AL ELECTRICAL CONDENSER Filed May 22,1934 FEEDEE'CK H POTTER RODERICK F. N ALPINE INVENTORS ATTORNEYSPatented Oct. 20, 1936 UNITED 'STATES PATENT OFFICE North Adams, Masscialties Company,

aasignors to Spragne Spe- North poratlon of Massachusetts Adams. Mass acor- Application May 22, 1934, Serial at. mass 7 2 claim. (01. 175-41)Our invention relates to electrical condensers and more particularly tonovel sealing means for such condensers.

As is known, the moisture-proof and air-tight 5 enclosure of electricalcondensers is of great im portance for their continued properperformance, and this applies to practically all types of electricalcondensers, as for instance, to waxor oilimpregnated paper condensersand to various types of electrolytic condensers.

A large number of constructions have been suggested and are availablefor the airand liquid-tight closure of such condensers.

The present invention relates to a novel'conplicity and low cost, and isespecially advantageous for mass production and with a view tostandardization.

It has the further advantage that it can be used for various types ofcondensers, as waxor oilimpregnated paper condensers, dry electrolyticcondensers, and even wet electrolytic condensers, with no changes orwith but such slight changes, as the addition of venting means for theescape of gases.

We shall describe our invention in connection with a specific embodimentthereof, as illustrated in the accompanying drawing, in which:

The figure is a vertical sectlonof a condenser embodying our invention.

The condenser assembly I0 is shown as a conventional wax-impregnated,rolled paper condenser, but as stated above, our invention is equallyapplicable to other forms and types of condensers.

The condenser-roll i0 comprises two electrode foils Ii-i i of tin oraluminum, which are separated in a conventional manner by single ormultiple layers of impregnated insulating material |2--|2. The condenseris shown as of the non-inductive type, in which one electrode foilextends beyond one end of the condenser-roll and the other electrodetoll extends beyond the other end of the roll. The protruding edges ofthe foils l|-l l are connected to terminal leads l2l2', respectively,which may be tinned copper wires. The connection may take place asshown, by forming a hook or a coil at the inner end of the wires|3--i3', which are then soldered at i4-l4- to the protruding end of therespective foil iill'. If desired the condenser-roll may be surroundedby an adhesive wrapping it to prevent its unwinding.

The condenser is surrounded by an open-ended cylindrical casing 22,preferably of metal, as

struction which has the advantage of great simaluminum 'or copper, thetwo ends of which are closed by composite sealing members 20-20. Asthese sealing members are shown as identical on both ends of thecondenser only one of them needs to be described.

The sealing member 20 consists of two circular washers, the inner washer2| being of fiber, bakelite, or other insulating material ofconsiderable mechanical strength and rigidity, and the outer circularwasher 22 being formed of soft rubber or other resilient material, whichis suitable as a gasket. The washer 22 is preferably somewhat thinnerand may have a slightly larger diameter than the washer 2|.

The washers 2| and 22 are provided with central apertures through whichpasses a cylindrical metal eyelet 23, the flanges 25-45 of which arecrimped around the two washers and hold them.

tightly together, to form a unit. This composite sealing membercomprising the stiff washer 2|, the resilient washer 22, and the eyelet23, forms a distinct unit of manufacture, which is marked by simplicityand low cost.

The terminal leads l2--l3' of the condenserroll are led through theholes 24-24 of the eyelets 22-23, whereas the free ends 28 of themetallic casing 28 are crimped inwards in a circular form around thewasher 22, forming therewith an air-tight seal. Where the lead l3emerges from the eyelet 23 it is soldered thereto, as shown at 26, thesolder 26 air-tightly sealing the eyelet opening 24. At the same timethe tension applied to the terminal l3, instead of being passed to thecondenser-roll, is taken up by the washer assembly.

To relieve the condenser-roll from pressure due or incident to thecrimping oi the casing ends 29 over the resilient washer 22, we preferto provide a cylinder 21, preferably of insulating material and ofsumcient stiffness, which serves both as a vertical distance piece andas an insulator between the condenser-roll l0 and the metallic casing28.

The washers 2|'2l against the cylinder 21, which is preferablyshouldered, as shown at 3!.

Instead of using a metallic casing which is open at both ends, one endof the casing may be closed and a single washer assembly provided. Insuch case the casing may serve as one electrode of the condenser. or thewasher assembly may be provided with two eyelets for the passage of thetwo electrodes. In case of multiple condensers of course a larger numberof eyelets can be provided.

are thereby abutting The sealing means thus described are very simple,easy to manufacture, and are especially advantageous in connection withcondensers oi comparatively small overall dimensions and which aremanufactured in mass production.

While we have described'our invention with respect to a specificconstruction and as used for. a condenser of specific type and form, wedo not wish to be limited to such construction and application, butdesire the appended claims to be construed as broadly as permissible in.view of the prior art.

What we claim as new and desire to secure by Letters Patent is:

1. An electrical condenser comprising a condenser assembly and twoterminal leads therefor, an open-ended metal casing surrounding saidassembly, a sealing member at each end oi said casing and comprising aninner plate of insulating material of considerable stiflness and anouter plate of soft rubber, an eyelet securing the said two plates toeach other, one of each oi said leads passing through said eyelet andbeing air-tightly soldered thereto, said open end oithecasingbeingcrimpedinto saidrubberplate to form an air-tight sealtherewith, and a rigid; tubular body'oi insulating material disposed.be-ftween the'oondenser assembly and the caslng,'; said inner platepressing against the ends 0! said; body and being held from inwarddisplacementj thereby;

2..An electrical condenser comprising a con-' denser assembly and aterminal lead therefor,

a cylindrical metal casing surrounding said assembly and being open atone end thereof, a,

sealing member at said open end of the casing and comprising an innerwasher of insulating. material of considerable stiffness, and an outerwasher of resilient gasket material, an eyelet se- I curing said twowashers to each other, said terminal lead passing through said eyeletand being 1 air-tightly soldered thereto, said open end of said casingbeing crimped into said outer washer to form an air-tight sealtherewith, and a rigid cylinder of insulating material disposed betweenthe condenser assembly and said casing, said inner washer pressingagainst said cylinder.

FREDERICK H. PO'1'1'ER. RODERICK F. MAOALPINE.

